The formation of a maize kernel requires growth coordination between embryo, endosperm, and surrounding maternal tissues. Key molecular actors in this coordination are hormones, sugars, peptides and transcription factors. Doll et al. review recent advances in our understanding of maize kernel development, drawing on genetic and –omics data. The authors also point out similarities and differences between seed development in Arabidopsis and maize (which has a much larger seed and a persistent endosperm). Mol. Plant 10.1016/j.molp.2017.01.008